Interpretive Summary: Campylobacter, a foodborne pathogen closely associated with poultry, is an important agent of human gastroenteritis in New Zealand. The pathways involved in the contamination of poultry flocks remain unclear, however, many vectors such as insects, rodents, and wild birds have been implicated. Infestation by insects, particularly darkling beetles, is difficult to control. Furthermore, darkling beetles are known vectors for a variety of pathogens that include Campylobacter, Salmonella, Infectious Bursal Disease, Aspergillus, E. coli, and Mareks. In this investigation, the relationship between darkling beetles and Campylobacter contamination of poultry flocks was investigated. Samples of beetles and of feces of the birds were cultured for the presence of Campylobacter spp.. A subset of the recovered isolates were genotyped. A large number of Campylobacter subtypes were isolated, suggesting that Campylobacter colonization of poultry is likely to arise from a number of different reservoirs. However, a set of genetically distinct isolates were found common to the broiler flocks and to the beetles. This research provides data which suggests that the darkling beetle may serve as a source of Campylobacter contamination of poultry. A more thorough understanding of the relationship between beetle infestation and the Campylobacter status of poultry flocks should enable progress in further development of biosecurity control measures.

Technical Abstract:
Campylobacter, a foodborne pathogen closely associated with poultry, is considered to be an important agent of human gastroenteritis in New Zealand. The pathways involved in the contamination of poultry flocks remain unclear, however, many vectors such as insects, rodents, and wild birds have been implicated. Shed infestation by insects, particularly darkling beetles (Alphitobius diaperinus), is difficult to control. Furthermore, darkling beetles are known vectors for a variety of pathogens that include Campylobacter, Salmonella, Infectious Bursal Disease, Aspergillus, E. coli, and Mareks. In this investigation, the relationship between darkling beetles and Campylobacter contamination of poultry flocks was investigated. A New Zealand breeder flock and four of its progeny broiler flocks were included in the study. Samples of beetles and of intestinal excreta of the birds were cultured for the presence of Campylobacter spp.. A subset of the recovered isolates were subsequently geneotyped using flaA SVR DNA sequence analysis. A large number of Campylobacter subtypes were isolated, suggesting that Campylobacter colonization of poultry is likely to arise from a number of different reservoirs. However, a set of genetically distinct isolates were found common to the broiler flocks and to the beetles. This research provides data which suggests that Alphitobius diaperinus may serve as a source of Campylobacter contamination of poultry. A more thorough understanding of the relationship between beetle infestation and the Campylobacter status of poultry flocks should enable progress in further development of biosecurity control measures.